I try to mix up my exercise so that I don't get bored & also it is working different muscles. I usually walk, ride & use the stepper for cardio. Then I usually do about 20 mins worth of squats/lunges & light weights for my upper body.

Go for a walk/jog that has hills and if possible stairs somewhere so you can jog up and down them. Try bike riding. maybe buy yourself some dumbells and do a few weight exersices at home, they won't make you look built but can tone you. You can buy some fairly cheaply at Target. Try a kickboxing dvd or something that you can do most days, they are usualy first half cardio then have situp and push ups at the end.